Damascene metal gate transistor technology - reduction of threshold voltage deviation and salicide integration to damascene gate process

摘要

We proposed the Damascene gate process in order to apply metal gate materials and high-k gate dielectrics to 0.1μm node high performance transistors. However, the deviation of crystal orientation of TiN barrier metals was found to affect threshold voltages of the Damascene gate MOSFETs. Therefore, we developed an inorganic CVD technique in order to control the crystal Orientation of TiN film. By using this technique, threshold voltage deviation and transconductance were drastically improved. On the other hand, Co salicide films on source/drain are required to be thermally stable because high temperature process is performed after salicide formation in the Damascene gate process. The Damascene metal gate MOSFETs with Co silicided source/drain were successfully formed because the agglomeration of CoSi{sub}2 films was reduced by ion implantation through salicide technique.